<?php

class bmp
{
    public $mpdf = null;

    public function bmp(&$mpdf)
    {
        $this->mpdf = $mpdf;
    }


    public function _getBMPimage($data, $file)
    {
        $info = array();
        // Adapted from script by Valentin Schmidt
        // http://staff.dasdeck.de/valentin/fpdf/fpdf_bmp/
        $bfOffBits=$this->_fourbytes2int_le(substr($data, 10, 4));
        $width=$this->_fourbytes2int_le(substr($data, 18, 4));
        $height=$this->_fourbytes2int_le(substr($data, 22, 4));
        $flip = ($height<0);
        if ($flip) {
            $height =-$height;
        }
        $biBitCount=$this->_twobytes2int_le(substr($data, 28, 2));
        $biCompression=$this->_fourbytes2int_le(substr($data, 30, 4));
        $info = array('w'=>$width, 'h'=>$height);
        if ($biBitCount<16) {
            $info['cs'] = 'Indexed';
            $info['bpc'] = $biBitCount;
            $palStr = substr($data, 54, ($bfOffBits-54));
            $pal = '';
            $cnt = strlen($palStr)/4;
            for ($i=0;$i<$cnt;$i++) {
                $n = 4*$i;
                $pal .= $palStr[$n+2].$palStr[$n+1].$palStr[$n];
            }
            $info['pal'] = $pal;
        } else {
            $info['cs'] = 'DeviceRGB';
            $info['bpc'] = 8;
        }

        if ($this->mpdf->restrictColorSpace==1 || $this->mpdf->PDFX || $this->mpdf->restrictColorSpace==3) {
            if (($this->mpdf->PDFA && !$this->mpdf->PDFAauto) || ($this->mpdf->PDFX && !$this->mpdf->PDFXauto)) {
                $this->mpdf->PDFAXwarnings[] = "Image cannot be converted to suitable colour space for PDFA or PDFX file - ".$file." - (Image replaced by 'no-image'.)";
            }
            return array('error' => "BMP Image cannot be converted to suitable colour space - ".$file." - (Image replaced by 'no-image'.)");
        }

        $biXPelsPerMeter=$this->_fourbytes2int_le(substr($data, 38, 4));	// horizontal pixels per meter, usually set to zero
        //$biYPelsPerMeter=$this->_fourbytes2int_le(substr($data,42,4));	// vertical pixels per meter, usually set to zero
        $biXPelsPerMeter=round($biXPelsPerMeter/1000 *25.4);
        //$biYPelsPerMeter=round($biYPelsPerMeter/1000 *25.4);
        $info['set-dpi'] = $biXPelsPerMeter;

        switch ($biCompression) {
          case 0:
            $str = substr($data, $bfOffBits);
            break;
          case 1: # BI_RLE8
            $str = $this->rle8_decode(substr($data, $bfOffBits), $width);
            break;
          case 2: # BI_RLE4
            $str = $this->rle4_decode(substr($data, $bfOffBits), $width);
            break;
        }
        $bmpdata = '';
        $padCnt = (4-ceil(($width/(8/$biBitCount)))%4)%4;
        switch ($biBitCount) {
          case 1:
          case 4:
          case 8:
            $w = floor($width/(8/$biBitCount)) + ($width%(8/$biBitCount)?1:0);
            $w_row = $w + $padCnt;
            if ($flip) {
                for ($y=0;$y<$height;$y++) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$w;$x++) {
                        $bmpdata .= $str[$y0+$x];
                    }
                }
            } else {
                for ($y=$height-1;$y>=0;$y--) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$w;$x++) {
                        $bmpdata .= $str[$y0+$x];
                    }
                }
            }
            break;

          case 16:
            $w_row = $width*2 + $padCnt;
            if ($flip) {
                for ($y=0;$y<$height;$y++) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$width;$x++) {
                        $n = (ord($str[$y0 + 2*$x + 1])*256 +    ord($str[$y0 + 2*$x]));
                        $b = ($n & 31)<<3;
                        $g = ($n & 992)>>2;
                        $r = ($n & 31744)>>7128;
                        $bmpdata .= chr($r) . chr($g) . chr($b);
                    }
                }
            } else {
                for ($y=$height-1;$y>=0;$y--) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$width;$x++) {
                        $n = (ord($str[$y0 + 2*$x + 1])*256 +    ord($str[$y0 + 2*$x]));
                        $b = ($n & 31)<<3;
                        $g = ($n & 992)>>2;
                        $r = ($n & 31744)>>7;
                        $bmpdata .= chr($r) . chr($g) . chr($b);
                    }
                }
            }
            break;

          case 24:
          case 32:
            $byteCnt = $biBitCount/8;
            $w_row = $width*$byteCnt + $padCnt;

            if ($flip) {
                for ($y=0;$y<$height;$y++) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$width;$x++) {
                        $i = $y0 + $x*$byteCnt ; # + 1
                        $bmpdata .= $str[$i+2].$str[$i+1].$str[$i];
                    }
                }
            } else {
                for ($y=$height-1;$y>=0;$y--) {
                    $y0 = $y*$w_row;
                    for ($x=0;$x<$width;$x++) {
                        $i = $y0 + $x*$byteCnt ; # + 1
                        $bmpdata .= $str[$i+2].$str[$i+1].$str[$i];
                    }
                }
            }
            break;

          default:
            return array('error' => 'Error parsing BMP image - Unsupported image biBitCount');
        }
        if ($this->mpdf->compress) {
            $bmpdata=gzcompress($bmpdata);
            $info['f']='FlateDecode';
        }
        $info['data']=$bmpdata;
        $info['type']='bmp';
        return $info;
    }

    public function _fourbytes2int_le($s)
    {
        //Read a 4-byte integer from string
        return (ord($s[3])<<24) + (ord($s[2])<<16) + (ord($s[1])<<8) + ord($s[0]);
    }

    public function _twobytes2int_le($s)
    {
        //Read a 2-byte integer from string
        return (ord(substr($s, 1, 1))<<8) + ord(substr($s, 0, 1));
    }


    # Decoder for RLE8 compression in windows bitmaps
    # see http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/bitmaps_6x0u.asp
    public function rle8_decode($str, $width)
    {
        $lineWidth = $width + (3 - ($width-1) % 4);
        $out = '';
        $cnt = strlen($str);
        for ($i=0;$i<$cnt;$i++) {
            $o = ord($str[$i]);
            switch ($o) {
            case 0: # ESCAPE
                $i++;
                switch (ord($str[$i])) {
                    case 0: # NEW LINE
                         $padCnt = $lineWidth - strlen($out)%$lineWidth;
                        if ($padCnt<$lineWidth) {
                            $out .= str_repeat(chr(0), $padCnt);
                        } # pad line
                        break;
                    case 1: # END OF FILE
                        $padCnt = $lineWidth - strlen($out)%$lineWidth;
                        if ($padCnt<$lineWidth) {
                            $out .= str_repeat(chr(0), $padCnt);
                        } # pad line
                         break 3;
                    case 2: # DELTA
                        $i += 2;
                        break;
                    default: # ABSOLUTE MODE
                        $num = ord($str[$i]);
                        for ($j=0;$j<$num;$j++) {
                            $out .= $str[++$i];
                        }
                        if ($num % 2) {
                            $i++;
                        }
             }
                break;
            default:
                $out .= str_repeat($str[++$i], $o);
        }
        }
        return $out;
    }

    # Decoder for RLE4 compression in windows bitmaps
    # see http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/bitmaps_6x0u.asp
    public function rle4_decode($str, $width)
    {
        $w = floor($width/2) + ($width % 2);
        $lineWidth = $w + (3 - (($width-1) / 2) % 4);
        $pixels = array();
        $cnt = strlen($str);
        for ($i=0;$i<$cnt;$i++) {
            $o = ord($str[$i]);
            switch ($o) {
            case 0: # ESCAPE
                $i++;
                switch (ord($str[$i])) {
                    case 0: # NEW LINE
                        while (count($pixels)%$lineWidth!=0) {
                            $pixels[]=0;
                        }
                        break;
                    case 1: # END OF FILE
                        while (count($pixels)%$lineWidth!=0) {
                            $pixels[]=0;
                        }
                        break 3;
                    case 2: # DELTA
                        $i += 2;
                        break;
                    default: # ABSOLUTE MODE
                        $num = ord($str[$i]);
                        for ($j=0;$j<$num;$j++) {
                            if ($j%2==0) {
                                $c = ord($str[++$i]);
                                $pixels[] = ($c & 240)>>4;
                            } else {
                                $pixels[] = $c & 15;
                            }
                        }
                        if ($num % 2) {
                            $i++;
                        }
             }
                break;
            default:
                $c = ord($str[++$i]);
                for ($j=0;$j<$o;$j++) {
                    $pixels[] = ($j%2==0 ? ($c & 240)>>4 : $c & 15);
                }
        }
        }
    
        $out = '';
        if (count($pixels)%2) {
            $pixels[]=0;
        }
        $cnt = count($pixels)/2;
        for ($i=0;$i<$cnt;$i++) {
            $out .= chr(16*$pixels[2*$i] + $pixels[2*$i+1]);
        }
        return $out;
    }
}
